Apparatus for fabricating fin-tube sheet assemblies



Dec. 14, 1943. E A. Y. GUNTER ET AL APPARATUS FOR FABRICATING FIN-TUBE SHEET ASSEMBLIES Filed Feb. 2, 1945 er e afar/ms.

INVENTORS Hdd/ s on Y Gunf Y Gear- J6.

NEY

Patented Dec. 14, 1943 APPARATUS FOR FABRICATIN G FIN-TUBE SHEET ASSEMBLIES Addison Y. Gunter, Larchmont, and George B. Farkas, Jackson Heights, N. Y., assignors to American Locomotive Company, New York,

N. Y., a corporation of New York Application February 2, 1943, Serial No. 474,418

1 Claim.

This invention relates to an apparatus for fabricating a fin-tube bundle and tube sheet assembly, and more particularly to a heat exchanger fin-tube bundle and tube sheet assembly in which the fins of the tubes are intermeshed.

An object of the present invention is to provide an apparatus for holding the tubes of a fin-tube bundle in intermeshed fin relation and for guiding the tubes into the tube orifices of a tube sheet for assemblage of the intermeshed fin-tubes with the tube sheet.

Referring to the drawing forming part of this application, Figure 1 is a plan view of a jig for holding fin-tubes, the fin-tubes being shown assembled in the jig; Fig. 2 is a side elevation of the jig and fin-tubes, with guide plugs disposed in the fin tubes and a tube sheet shown in section with the plugs in position for guiding the fin-tubes into tube sheet orifices; Fig. 3 is a. foreshortened elevation of a guide plug with a portion of a fin-tube assembled therewith shown in section; and Fig. 4 is an isometric View of a bundle of intermeshed fin-tubes assembled with a tube sheet, the tube sheet being shown fragmentally.

The present invention is directed to the solution of the problem of assembling a bundle of intermeshed cross-fin-tubes with a tube sheet. It is impossible to connect the fin-tubes of such a bundle with the tube sheet one at a time, due to the fact that the intermeshing of the fins prevents axial movement of one tube relative to another. Therefore the entire bundle of fin-tubes must be intermeshed first and then moved as a unit into the orifices of the tube sheet. It will be obvious that this can not be accomplished without diiiiculty unless some apparatus for registering the fin-tubes with the tube sheet orifices is provided.

The fin-tubes are indicated in the drawing by the reference numeral I, and each includes a tube portion and external horizontal cross-fins. The fins of the different tubes of the bundle are all equally spaced, but the first (top) fin of some tubes is farther from the top of the tube than others, this providing offsetting of the fins for intermcshing purposes.

The jig or form 2 may be made as a casting, or it may be built up of wood or other suitable material. It has a bottom 3 providing seats for supporting tubes, but it may, if desired, be open at the bottom and be rested on a base when in use, the base then forming the jig bottom providing the tube seats. It is open at the front 4, has side walls 5 and 6 and a rear wall I. The walls are cylindrically concavely recessed, as will later more fully appear, to snugly receive and place the outer fin tubes, as is clearly shown in Fig. 1.

In assembling the fin-tubes with the jig, and referring more particularly to Fig. 1, the tubes would be inserted, in their vertical upright position, through the open front 4 into the hollow interior or chamber of the jig, in alphabetical order from a to l, as indicated in Fig. 1, there being recesses, a, b, c, d, e, 7" and i for the tubes a, b, c, d, e, and 2', respectively.

The bundle, once assembled in the lie, can only be removed through the open top 8 through which the tubes extend as the recesses prevent bodily movement of the bundle through the open front 4. The tops of the fin-tube would all be in the same horizontal plane as shown in Fig. 2.

After the bundle is assembled in the jig, plugs 9, best shown in Fig. 3, are inserted in th top end of the tubes. Each plug 9 has a cylindrical body I 0 provided with a tapered upper end H, the cylindrical portion of the body being of a diameter to slide snugly through a tube sheet orifice and equal to the outside diameter of the tube with which it is used, and a smaller stem or shank l2 of a diameter to slide snugly inside the tube with which it is used, ther being a shoulder l3 between the stem l2 and body l0, adapted to seat on the top end face of the tube with which it is used.

When the plugs, tube bundle and jig are assembled, then assemblage with a tube sheet I4 may be accomplished by movement of the tube sheet toward the jig, the tapered ends II registering in appropriate tube sheet orifices l5, prearranged in accordance with the arrangement of the seats for the tubes, centering the plugs with the tube sheet orifices and guiding the bodies l0 through the orifices, and thereafter the tops of the tubes through the orifices. The plugs may then be removed by lifting them out of the tubes, and the jig may be removed by dropping it from the tubes, or the jig may be left with the tubes until they are secured in the tube sheet orifices, as by expanding or welding.

While horizontal cross-fin-tubes have been described and shown in the drawing the invention is equally applicable to fin-tubes provided with helical cross-fins, cross-fins being used in this broader sense in the claim.

While the jig has been shown with the front open, if desired it may be closed at the front and the chamber made larger to provide a sufiicient space adjacent the front so that the fin-tubes can be dropped vertically into the chamber through the open top and then moved sidewise into finintermeshed position.

A completed fin-tube bundle and tube sheet assembly is shown in Fig. 4. A heat exchanger employing this type of assembly is shown in a copending application of Gunter, Farkas & Shaw, Serial No. 474,417, filed February 2, 1943.

While there has been hereinbefore described an approved embodiment of the invention, it will be understood that many and various changes and modifications in form, arrangement of parts and details of construction thereof may be made without departing from the spirit of the invention and that all such modifications as fall within the scope of the appended claim are contemplated as part of this invention.

The invention claimed and desired to be secured by Letters Patent is:

A former for use in building up a bundle of cross-fin-tubes preparatory to simultaneously inserting, in the orifices of a tub sheet, the ends of said tubes at one end of said bundle, adjacent tubes of said bundle having their fins respectively in intermeshing relation to each other, said former comprising a horizontal unobstructed base substantially equal in area to the base of said bundle of tubes to be built up for supporting said tubes in vertical position upon their opposite ends; a side wall; and another side wall adjacent said first mentioned side wall, said side walls extending upwardly from and at right angles to said base for affording lateral supports for said bundle 'at corresponding sides thereof, said walls having each a plurality of vertical cylindrically-concave seats for engagement with the fins of adjacent tubes of said bundle, said former having an open top opposite and equal in area to said base for permitting said bundle to protrude upwardly therefrom and open at one side from said base to said top for permitting said tubes to be passed therethrough laterally to their respective bundle positions in said fin-intermeshing relation within said former.

ADDISON Y. GUNTER. GEORGE B. FARKAS. 

